Pressure differential responsive valve means



Se t. 12, 1967 S STRAUSS ET AL 3,340,898

PRESSURE DIFFERENTIAL RESPONSIVE VALVE MEANS ori inal Filed July 27,1962 TO 32 ADJUSTING INVENTORS THEODOR STRAUSS BY WlLHELM BACHMANN ATTUENE) United States Patent Ofiice 33411898 Patented Sept. 12, 1967 4Claims. (Cl. 137-627.5)

ABSTRACT OF THE DISCLOSURE A pressure differential responsive valvemeans having a diaphragm subjectable on opposite sides respectively toseparate control pressures and operative to cause supply of fluid underpressure to a receiver only when the separate pressures aresubstantially equal, and operative to cause venting of fluid underpressure from the receiver whenever the separate pressures are unequal.

The present application is a division of the copending application, nowPatent 3,165,121, issued Jan. 12, 1965 and assigned to the sameassignee.

In the propulsion of ships, it is common practice to control the angleof incidence of the propeller blades either pneumatically orhydraulically to thereby control direction of travel and speed of theship. This control of the propeller occurs by means of a pressureactuated adjusting device which is usually located in the propellershaft alley and controlled by a plurality of control valves, one ofwhich is located on the bridge control stand and the other is located onthe engine room control stand. The selection of the operating controlvalve to be effective is under the control of a multiple position cockor similar device usually located in the engine room which operablyconnects either the one control valve or the other control valve withthe adjusting device.

By means of this arrangement just described, it is possible that controlof the adjusting device may be attempted to be applied undesirably byboth control valves simultaneously. For example, if an attempt be madeto operate the control valve on the bridge control stand to give apropeller angle of incidence of a positive angle, and concurrently thecontrol valve on the engine room control stand be operated to adjust theangle of incidence of the propeller to a negative angle, a severedamaging shock on the driving engines and the propeller shaft and gearsassociated therewith would occur.

The present invention provides a presure differential responsive valvefor preventing changeover of the multiple position cock unless thecontrol pressures supplied by both of the control valves are equalized.

According to the present invention, there is provided an equal pressurevalve for use in a multiple station control apparatus whereby a manuallyoperated rotatable plug valve of a multiple position cock is locked inone position if the fluid pressures which are supplied thereto by twocontrol valves are of unequal degree as determined by said equal presurevalve, and said plug valve in the multiple position cock body isunlocked and can be repositioned if the fluid pressures supplied theretoare of equal degree as determined by said equal pressure valve. Themultiple position cock can therefore be repositioned under the controlof the equal pressure valve only when fluid pressures supplied theretofrom the two control valves are substantially equal. The equal pressurevalve has a diaphragm therein activated on one side by the fluidpressures delivered from one control valve, and on the other side by thefluid pressures delivered from the other control valve in a manner thatwhen the fluid pressures on both sides of said diaphragm are equal, asource of fluid under pressure is connected to a locking cylinder on thebody of the multiple position cock to unlock the multiple position cockfor changeover operation.

In the accompanying drawings, FIG. 1 is a diagrammatic view of theapparatus showing the two control valves and the multiple position cockunder the control of an equal pressure valve.

FIG. 2 is an enlarged diagrammatic sectional view showing details of theequal pressure valve of FIG. 1.

Description Referirng to FIG. 1, the apparatus includes a bridge controlvalve 1, an engine room control valve 2, a pressure differentialoperated valve means referred to hereinafter as an equal pressure valve3, and a multiple position cock 4, all interconnected by appropriatepiping supplied with fluid under pressure from a supply reservoir 5. Thebridge control valve 1 is manually operated by a handle 6 whereby supplyof fluid under pressure from the reservoir 5 flows from a pipe 7 throughsaid control valve, as indicated by a dotted line, to a pipe 8 at apressure determined by the positioning of the said handle 6 from a fullpressure position shown to another position (not shown) whereby pipe 8is connected through said control valve to atmosphere at a port 9. Theengine room control valve 2 is manually operated by a handle 10 wherebyfluid under pressure is supplied from the reservoir 5, pipe 7, a pipe11, through said control valve, as indicated by a dotted line, to adelivery pipe 12 at a pressure determined by the positioning of thehandle 10 from a full pressure position shown to another position wheresaid delivery pipe 12 is connected therethrough to atmosphere at anexhaust port 13.

The multiple position cock 4, in this instance a twoposition, three-waycock, includes a valve body 14 and a plug valve 15 whereby said plugvalve 15 is rotatably positioned within the valve body by movement of avalve handle 16 connected to the plug valve by means not shown. Thevalve body 14 is provided with three radial passages 17, 18 and 19,passages 17 and 19 connecting to the delivery pipes 8 and 12,respectively, while passage 18 is connected to a pressure actuatedadjusting device (not shown) for adjusting the pitch or angle ofincidence of the propeller blades according to the degree of pressuresupplied thereto, the details of the adjusting device being notnecessary to an understanding of the present invention. Also included inthe valve body is a guide slot 20, explained hereinafter. The plug valve15 has a recessed or feed groove 21 of a length to selectively connecteither passages 17 and 18, or passages 18 and 19 (as shown in brokenlines), according to the rotative position of said plug valve. Twolocking slots 22 and 23, explained hereinafter, are also in the plugvalve 15.

Associated with the multiple position cock 4 is a locking cylinder 24suitably mounted by means (not shown), such that a piston stem 25 of apiston 26 slidably mounted therein may align with the locking groove 20to extend therethrough into one or the other of the locking slots 22 or23. The piston 26 in said locking cylinder forms a fluid pressurechamber 27 on one side thereof and a spring chamber 28 on the other sidethereof for housing a spring 29. The chamber 27 is connected by a pipe30 to the equal pressure valve 3. The spring chamber 28 is vented toatmosphere at a port 31 to permit free movement of the piston 26- whensubject to fluid under pressure in the chamber 27.

The equal pressure valve 3, besides being connected to the lockingcylinder 24 by way of pipe 30 as previously described, is also connectedto the passages 17 and 19 in the valve body 14 of the multiple positioncock 4 by pipes 32 and 33, respectively, and to the supply reservoir byway of pipe 34 and pipe 7. The equal pressure valve 3 is comprised of ahousing 36 divided into two portions joined together by suitable meanssuch as bolts 37 through flanges formed thereon to secure therebetween adiaphragm 38. The diaphragm 38 separates the interior of the housinginto two chambers, chamber 39 supplied with fluid under pressure frompipe 32, and chamber 40* supplied with fluid under pressure from pipe33. An axially movable rod 41 is connected through the center of thediaphragm at two face plates 42 and 43 on either side of said diaphragm,the ends of said rod slidably extending into bores 44 and 45 formed inthe housing. The face plates 42 and 43 are secured together with thediaphragm 58 between them by any suitable means such as rivets or screwswith either one of said plates being secured to the rod 41 as bywelding, to thereby effect transmittal of any movement of the diaphragmto the rod 41. On the lower side of the diaphragm 38 within the chamber40 are positioned two movable spring cups 46 and 47 slidably mountedwithin a groove 48 in the internal surface of the housing and securedtherein by a snap ring 49'. Interposed between the two spring cups undercompression and encircling the rod 41 is a spring 50 which exerts abiasing force outwardly on the spring cups in a manner to position thespring cups at the outer edges of the groove 48 to maintain thediaphragm 38 in its centered position as shown. A locking plate 51encircles the rod 41 below one of the spring cups 4'] and is secured tosaid rod such that raising movement of said rod will be opposed by thespring 50 acting against the spring cup 47 and locking plate 51.Lowering movement of the rod 41 is opposed by the spring 50 actingagainst the spring cup 46 and face plate 43.

A third chamber identified herein as the regulating chamber 52 is formedwithin the chamber 39 on the upper portion of the housing 36, saidchamber comprising a slide valve bore 53 and a spring chamber 54.Slidably positioned within the slide valve bore 53 is a hollow pistonstem 55 of a piston 56. The hollow piston stem 5-5 acts as a slide valvein the bore 53 and contains a chamber 57 with an outlet 58 on thesliding portion of said stem to positionably align with an exhaust port59 in the housing 36 when the piston and piston stem are moved to theirleft-most position, as shown in the drawing and explained hereinafter.The chamber 57 also has an outlet or exhaust port 60 in the face of thepiston 56 which opens into the spring chamber 54. A spring 61 isinterposed between the face of the piston 56 and a portion of thehousing 36'. An intake port 63 is also formed in portion of the housing36. An intake and exhaust valve 64 is located in the spring chamber andcomprises a stem 65 with an exhaust valve ball 66 on one end thereofadaptable to seat in the port 60 in the face of the piston 56 and anintake valve ball 67 on the other end of the stem 65 adaptable to seatin the intake port 63. A spring 68 biases the intake and exhaust valvetowards the face of the piston or in a left-hand direction as seen inthe drawing. Intake chamber 69 connects the intake port 63 to the pipe34.

Suitably attached to the housing 36 to the left of the piston 56 andhollow piston stem 55 is a pivot mounting 70 to which is pivotallysecured a two-arm crank lever 71. The upper end of the twoarm lever 71isformed in a ball-shaped knob 72 to abut the end of the piston stem 55.The lower arm of the two-arm lever 71 is formed in a ball-shaped knob 73to ride on a two-surface cam 74 on rod 41. Cam 74 has a high surface 75with two tapered surfaces on either side of the high surface 75decreasing in diameter towards the diameter of the rod 41. The uppertapered surface is identified as surface 76, the lower tapered surfacebeing surface 77. This cam is securely mounted in an encircling mannerabout the rod 41 for operational purposes described hereinafter.

Operation In operation, the apparatus shown in FIG. 1 is supplied withfluid under pressure from the charged reservoir 5 via the pipe '7 andthrough both the bridge control valve It and the engine room controlvalve 2 via pipe 11 when both said control valves 1 and 2 are in theirrespective full pressure positions as shown, with handles 6 and 15 intheir right-hand positions. With the handles 6 and 1h positioned as justdescribed, equal fluid pressures are supplied by pipes 8 and 12 to pipes32 and 33 respectively, thereby effecting an equal fluid pressure supplyto chambers 39 and 4h on opposite sides of the diaphragm 38 of the equalpressure valve 3. With equal pressures in the chambers 39 and 41), theequal pressure valve 3 is centrally positioned, as shown, to establishcommunication between the pipes 34 and 30 in a manner now described.Equal pressure on opposite sides of the diaphragm 33 permits the spring5% between the spring cups 46 and 4-7 to position the diaphragm andconnected axial rod 41 to a center position as shown, wherein the highsurface of the cam 74 on the rod 41 engages the ballshaped knob '73 ofthe lower arm of crank lever 71. With the high surface 75 of the cam 74engaging the crank lever 71, said crank lever is pivoted clockwise aboutthe pivot mounting 7t in a manner that the ballshaped knob '72 engagesthe hollow piston stem 55 of piston 56 and moves said piston and stem toa right-hand position against the force of spring 61, as shown. With thepiston 56 in its right-hand position, the face of the piston 56 engagesthe exhaust valve ball 66 at the port 69 to close said port 60 and alsomove the entire intake and exhaust valve 64 to the right against theforce of the spring 68 to move the intake valve ball 67 away from theintake passage 63 to thereby permit fluid under pressure to flow fromthe reservoir 5, pipe 7 and pipe 34, through the chamber 69, passage 63and chamber 54 to the pipe 30.

Supply of fluid under pressure to pipe 30 as just described establishesa supply of fluid under pressure to the chamber 27 of the lockingcylinder 24 to effect movement of the piston 26 and piston stem 25 to aleft-hand position, as shown, in opposition to the force of the spring29. Movement of the piston stem 25 leftward in the guide slot 20 of thevalve body 14- of the multiple position cock 4 releases the said pistonstem from seating in one or the other of the locking slots 22 or 23 suchthat the plug valve 15 may be rotated to either position A or B(indicated at the handle 16) as desired to supply fluid under pressureto passage 13 selectively from either passage 17 or 19 and feed groove21.

Although the handles 6 and 10 are shown and described herein as in theirrespective full pressure positions, operation of the equal pressurevalve 3 to supply fluid under pressure to the locking cylinder 24 can beeffected in a like manner regardless of the positioning of the twohandles 6 and M as long as they are both positioned to supply equalfluid pressures. For example, assume the pressures of fluid supplied tothe pipes 8 and 12. are decreased from a pressure of say 60 psi. towarda zero pressure as the handles 6 and 15, respectively, are moved to theleft in a counterclockwise motion. Also assume a pressure of 10 p.s.i.supplied to the passage 18 of the multiple position cock would cause theadjusting device (not shown) to cause the propeller pitch to be at oneextreme angle of incidence indicating a full ahead speed, and a pressureof 60 p.s.i supplied to the passage 18 of the multiple position cock'would cause the adjusting device to cause the propeller pitch to be atan opposite extreme angle of incidence indicating a full astern speed,with the angle of incidence adjustable from one extreme (full ahead) tothe opposite (full astern) as the fluid pressure supplied to passage 18is increased. Thus, if both handles 6 and 10 were at any like positionssupplying any equal pressures, the multiple position cock could berotated to shift control from the engine room to the bridge and viceversa. If, however, one of the handles, say handle 6, is positioned tosupply a low fluid pressure (which would result in a high speedforward), and the handle were positioned to supply a high fluid pressure(which would result in a high speed astern), the unequal pressuressupplied to the equal pressure valve would prevent movement of themultiple position cock and thereby prevent shifting of control from onecontrol valve to the other, in a manner now described;

If the fluid pressures supplied to the pipes 32 and 33 are unequal, itcan be seen that the fluid pressures in the chambers 39 and 40 willlikewise be unequal to cause the diaphragm 38 and connected rod 41 to bemoved vertically either upward or downward, dependent on which of thefluid pressure in the chambers 39 and 40 predominates. The resultantvertical movement of the rod 41 and cam 74 will permit the ball-shapedknob 73 of the lever 71 to ride down one or the other of the taperedsurfaces 76 or 77 of the cam 74, dependent on the direction of verticalmovement of the rod 41, to cause counterclockwise rotation of the lever71 due to the force of the spring 61 acting leftward through the piston56 against the ballshaped knob 72 on the lever 71.

When the lever 71 moves counterclockwise as just described, the piston56 simultaneously moves to a lefthand position in which a series ofdifferent events occur simultaneously, as follows:

(a) the spring 68 acting on the exhaust valve ball 66 moves the intakeand exhaust valve 64 to the left with the moving piston 56 until theintake valve ball 67 seats in the passage 63 to prevent further supplyof fluid under pressure therethrough,

(b) once the intake valve ball 67 is seated, continued movement to theleft of the piston 56 by the spring 61 moves the piston face and thepassage 60 therein away from the exhaust valve ball 66 to open thepassage 60 between the chamber 54 and the chamber 57 in the piston stem55, and

(c) the outlet 58 in the piston stem 55 aligns with the exhaust port 59in the housing 36.

It can thus be seen that the leftward movement of the piston 56 eifectscutoif of the supply of fluid under pressure from pipe 34 to the chamber27 of the locking cylinder moving the stem 25 through the groove to seatin either one of the locking grooves 22 or 23, determined by positioningof the plug valve 15 by rotary movement of the handle 16, to cause theplug valve 15 to be locked in the position desired.

Rotary movement of the plug valve 15 can thus be effected only when thehandles 6 and 10 of the respective control valves 1 and 2 are positionedto supply fluid under equal pressures to the respective pipes 32 and 33to in turn reposition the diaphragm 38 of the equal pres- Sure valve 3to its central position described hereinbefore.

Although this apparatus is described herein as utilized in a controlsystem adapted to shipboard operation, it can be seen that it could bereadily adapted for other control systems for other adjusting devices,as for example motor controls in locomotives with two engineers controlstations.

Having now described the invention, what we claim as new and desire tosecure by Letters Patent, is:

1. Pressure differential operated valve apparatus comprising:

(a) a valve body having a fluid pressure supply port,

a fluid pressure delivery port and a fluid pressure vent port,

-(b diaphragm means secured in said valve body and subject to fluidunder pressure from one source on one side and subject to fluid underpressure from a second source on the other side, said diaphragm meansbeing opera'bly responsive to equal fluid pressures on said one side andsaid other side to assume one position operably responsive to a greaterfluid pressure on said one side than on said other side to assume asecond position, and operably responsive to a greater pressure on saidother side than on said one side to assume a third position,

(c) valve means operable to one position to establish communication viawhich fluid under pressure is supplied from said supply port to saiddelivery port and operable to a second position to establishcommunication via which fluid under pressure flows from said deliveryport to said vent port,

(d) rod means coaxially connected to and extending through saiddiaphragm means in a manner that movement of said diaphragm means istransmitted to said rod means, and

(e) position transmitting means operable responsively to movement ofsaid rod means and eifective when said diaphragm means is in said oneposition to cause positioning of said valve means in its said oneposition and effective when said diaphragm means is in said second orthird position to cause positioning of said valve means in its saidsecond position.

2. Pressure diiferential operated valve apparatus comprising:

(a) valve body means having a fluid pressure supply port, a fluidpressure delivery port, and a fluid pressure vent port,

(b) diaphragm means secured in said valve body and subject to fluidunder pressure from one source on one side and subject to fluid underpressure from a second source on the other side, said diaphragm meansbeing operably responsive to equal fluid pressures on said one side andsaid other side to assume one position operably responsive to a greaterfluid pressure on said one side than on said other side to assume asecond position,

(c) valve means operable to one position to establish a? fluid pressuresupply communication via which fluid under pressure is supplied fromsaid supply port to said delivery port and operable to a second positionto establish communication via which fluid under pressure flows fromsaid delivery port to said vent port,

(d) two-armed lever means pivotably secured within said valve body meansabutting said valve means at a first arm,

(e) rod means coaxially connected to and extending through saiddiaphragm means in a manner that movement of said diaphragm istransmitted to said rod means, and

(f) cam means connected to said rod means, said cam means abutting asecond arm of said lever means and effective when said diaphragm meansis in said one position to cause positioning of said valve means in itssaid one position and effective when said diaphragm means is in saidsecond position to cause positioning of said valve means in its saidsecond position.

3. Pressure diiferential operated valve apparatus, as claimed in claim2, further characterized by a spring means abutting said valve means toposition said valve means in said second position when said diaphragmmeans and connected rod means are in their said second position.

4. Pressure differential operated valve apparatus comprising:

(a) valve body means having a fluid pressure supply port, a fluidpressure delivery port, and a fluid pressure vent port,

(b) diaphragm means secured in said valve body means and subject tofluid under pressure from one source on one side and subject to fluidunder pressure from a second source on the other side, said diaphragmmeans being operably responsive to equal fluid pressures on said oneside and said other side to assume one position and being operablyresponsive to a greater fluid pressure on said one side than on saidother side to assume a second position,

(c) piston and piston stem means,

(d) valve means operable cooperatively with said piston and piston stemmeans to one postion to establish communication via which fluid underpressure flows from said supply port to said delivery port and operablycooperatively with said piston and piston stem means to a secondposition to establish communication via which fluid under pressure flowsfrom said delivery port to said vent port,

(e) two-armed lever means pivotally mounted within said valve body meansabutting said piston and pistOn stem means at a first arm,

(f) rod means coaxially connected to and extending through saiddiaphragm means in mannerthat movement of said diaphragm is transmittedto said rod means, and

(g) cam means connected to said rod means, said cam means abutting asecond arm of said lever means and effective when said diaphragm meansand connected rod means are in said one position to cause positioning ofsaid piston and piston stem means and said valve means in their said oneposition effective when said diaphragm means and connected rod means arein said second position to cause positioning of said piston and pistonstem means and said valve member means in their said second position.

References Cited UNITED STATES PATENTS 11/1953 Carlson. 1/ 1954 Drinker.

1/1962 Parks 137627.5

CLARANCE R. GORDON, Primazy Examiner.

1. PRESSURE DIFFERENTIAL OPERATED VALVE APPARATUS COMPRISING: (A) AVALVE BODY HAVING A FLUID PRESSURE SUPPLY PORT, A FLUID PRESSUREDELIVERY PORT AND A FLUID PRESSURE VENT PORT, (B) DIAPHRAGM MEANSSECURED IN SAID VALVE BODY AND SUBJECTED TO FLUID UNDER PRESSURE FROMONE SOURCE ON ONE SIDE AND SUBJECT TO FLUID UNDER PRESSURE FROM A SECONDSOURCE ON THE OTHER SIDE, SAID DIAPHRAGM MEANS BEING OPERABLY RESPONSIVETO EQUAL FLUID PRESSURES ON SAID ONE SIDE AND SAID OTHER SIDE TO ASSUMEONE POSITION OPERABLY RESPONSIVE TO A GREATER FLUID PRESSURE ON SAID ONESIDE THAN ON SAID OTHER SIDE TO ASSUME A SECOND POSITION, AND OPERABLYRESPONSIVE TO A GREATER PRESSURE ON SAID OTHER SIDE THAN ON SAID ONESIDE OF ASSUME A THIRD POSITION, (C) VALVE MEANS OPERABLE TO ONEPOSITION TO ESTABLISH COMMUNICATION VIA WHICH FLUID UNDER PRESSURE ISSUPPLIED FROM SAID SUPPLY PORT TO SAID DELIVERY PORT AND OPERABLE TO ASECOND POSITION TO ESTABLISH COMMUNICATION VIA WHICH FLUID UNDERPRESSURE FLOWS FROM SAID DELIVERY PORT TO SAID VENT PORT,